1. Field of the Invention
The present invention relates to a duct structure for watercraft. More specifically, the present invention relates to a duct structure for an air intake duct for watercraft.
2. Description of the Related Art
Personal watercraft have become very popular in recent years. This type of watercraft is quite sporting in nature and carries a rider and possibly one, two, three, or four passengers. A relatively small hull of the personal watercraft commonly defines a rider's-area above an engine compartment. An internal combustion engine-frequently powers a jet propulsion unit which propels the watercraft. The engine is disposed within the engine compartment in front of a tunnel provided on the underside of the watercraft hull. The jet propulsion unit is located within the tunnel and is driven by the engine.
Air ducts typically communicate air into the engine compartment for induction by the engine and to ventilate the engine compartment.
FIG. 8 illustrates a known air duct structure. Each air intake duct 78 includes a rigid pipe 70, made of hard plastic, extending through the deck 16 of hull 12 and terminating at a first end 72. A flange 74 disposed around the pipe 70 abuts a portion of the deck 16. Fasteners, such as rivets 76, for example, extend through the flange 74 and the deck 16 to secure the pipe 70 to the deck 16.
An elbow 78 of the pipe 70 directs the pipe 70 downwardly and slightly forwardly into the engine compartment. A flexible pipe 80 is attached to a second end 82 of the rigid pipe 70 and can be configured so as to communicate with any desired location within the hull 12.
The air duct structure shown in FIG. 8 is quite complicated as seen by the number of parts required to form the duct stricture. Further, this duct structure has a high production cost and is difficult to assemble. More specifically, the flange 74 must be secured to the deck 16 by rivets 76 to secure the air duct structure, and the air duct structure includes two separate pipes 70, 80 that must be joined to each other.